Method of treating wooden poles and the like



Oct. 12 1926.

R. D. PRITTIE METHOD 0F TREATING WOODEN POLES AND THE LIKE Filed Feb. 28, 192s Il! Irl u l l 'www um l|| HI 'l Humm l...-

lllllll mill ll llllllll l mill nmllm' l' Illllll I Patented oct. 12, 192s;

UNITED STATES 1,602,933y PATENT OFFICE. i

RALPH DOWNEY PBITTIE, OF CALGARY, ALBERTA, CANADA, ASSIGNOB T0 JAMES H. DIXON, 0F CALGARY, ALBERTA, CANADA.

METHOD 0F TBEATIN G WOODEN PQLES AND THE LIKE.

This invention relates to a process and apparatus for treating with the same kind ortwo diiferent kinds' of liquid preservatives, wooden telegraph and telephone poles, piling, posts land similar pieces 4orsticks` of wood` so as to treat one end of the pole which is let linto the ground with a heavy and strong liquid preservative and the opposite end of the same which is above ground with a light and weak liquid preservative and thus treat the different parts of the same in accordance with the exposure to decay of the respective parts.

The object of this invention is to provide a method and apparatus, whereby wooden poles may be treated with liquid preservatives of`dierent strength at opposite ends thereof efficiently, economically and'expeditiously and insure a product which is de pendable and of uniform quality.

In the accompanying drawings:

Figure 1 is a diagrammatic sectional elevation 'of an apparatus containing my improvements and suitable for practicing this method. .Figure 2 is a fragmentary sectional elevation showing a preferred means for -handling lthe poles in groups or bundles. Figure 3 is a vertical section showing a modified arrangement-of the impregnating tank. i

Similar characters of reference refer to like parts throughout the several views.

A suitable apparatus embodying my invention and adapted for practicing my improved method is shown in Fig. 1 and constructed as follows:

l represents' an upright treating or impregnating tank or chamber which is adapted to receivefin a vertical position the poles, piles, posts 2 or the like, to be treated with a heavy or strong liquid preservative, this tank being preferably sufficiently large in diameter to receive a plurality of such poles, which are arranged side by ,side in a group.

100 represents an upright treating or impregnating ltank or chamber which is adapted to rec'eive, in an upright position the poles, piles, posts 2, or the like, to be treated with a light or wea-k liquid preservative, this.

tank being also suicientlydarg in diameter to receive a group or bundle of such poles.

In its preferred form, each of these tanks comprises an' upright cylindrical body or Jwall 3,-a flat bottom 4 which is secured to the lower end of the. wall, and 'a movable Application led February 28, 1223. Serial No. 621,951.

Wooden poles ofV normal or commercial lengths. Tanks having a height of about forty feet and a diameter of about eight feet will be found at present to answer all practical purposes. These tanks or vats may either rest with their lower ends 1upon the surface of the eartli or this same may be let into the ground more or less to snit conditions or requirements. For the purpose of permlttinr the operators to manlpulate the covers or lids at the top of the impregnating tanks for opening and closing the same, a platform or gallery 8 is preferably mounted around the upper parts of the tanks and an upright ladder 9 is arranged at one side wall of the same for the purpose of enabling the attendants to easily reach the gallery or platform from the ground.

Various 7preservatives may be employed for treating the wooden'poles heavily and strongly, for instance, liquid creosote having a strong` high, or powerful protective capaclty may be employed for treating the butt ends of poles which are let into the ground and liquid zinc-chloride may be employed for treating those-parts of the top portions of the poles which are arranged above the ground when in use and not subject to as great a decay as that part of the pole which comes in contact with the ground.

A supply of liquid creosote may be obtained from any suitable source but preferably from a. reservoir 10 from which the creosote is drawn into the lower part of the creosote impregnating or treating tank or vat and to which the unused part of the creosote is again returned, after a group of poles have been treated; This may be accomplished by a pump and piping-of any suit-ly able construction and`arrangement and in* the present instance comprises a pump 11 which has its inlet 12 connected b means of branch pipes 13, 14 with a main plpe 23 leading` to the lower part of the impregnating tank, while its outlet 16 is' connected by means of branch pipes 17, 18 with the creosote reservoir and the main pipe 23, uthese several branch pipes being provided with valves 19, 20, 21, 22, so that the pump may be utilized either for delivering liquid creosote from this reservoir to] the creosote impregnating tank or the surplus creosote may be returned from this impregnating tank or the surplus creosote may be returned from this impregnating tank to the supply reservoir 10, by properly manipulating the valves arranged in the piping which connects this pump with the reservoir and impregnating tank.

Inasmuch as only the butt ends of the poles need to be heavily treated with creosote the lowery end of the creosote impregnating tank is only filled to such a height as it is desired to protect the butt ends of the poles` a height of approximately five feet being sufficient for this purpose. A pressure gage 24 is preferably connected by means of a pipe with theinterior of the creosote impregnating tank at a point adiacent to the level of the creosote, and asafety valve 25 is preferably connected with the upper part of the creosote impregna-ting tank, thereby enabling the operator to note the pressure within the tank and also to permit any excess pressure tovescape therefrom so that the operation of the apparatus may be conducted without endangering 4Uthe workmen.

The creosote in the lower part of the creosote 4impregnating tank may be, heated so as yto preserve the same in a highly fluid condition and also cause the same to penetrate the wooden poles to the maximum extent, which heating may lbe accomplished in various ways, for instance, by means of a pipe coil 26 arranged in the lower part of the impregnating tank adjacent to the wall thereof and around the space which is occupied by the lower or butt ends of the posts, which coil may receive any suitable heating agent. such. as hot water, steam or the like. This heating agent mav be supplied from any -suitable source and the admission of the same to the coil may be controlled by means of a hand valve 27. If desired` the creosote vapors rising from the .heated liquid creosote into the upper part of the impregnati-ing chamber may operate either alone on the top portions ofthe poles or the same may be additionally heated by steam which is supplied thereto by means of a pipe 28 entering the impregnating chamber at a short distance above the normal creosote level and provided with a valve 92 for controlling the same.

At certain times in the operation of this apparatus it is vdesirable to produce a pressure in the impregnating tank in addition to any pressure whichlmay be caused therein by the heat of the coil 26 and the heatpof the steam supplied by the pipe 28 for the purposeof forcing the liquid creosote into the pores or interstices of the butt ends or lower portions thereof. At other times a vacuum is created within the impregnating chamber for the purpose of withdrawing the excess or surplus creosote from the butt ends of /poles and thus permit ofsaving the excess material and utilizing it for the treatment of other poles. Although various means may be employed for` thus creating a pressure within the impregnating chamber or tank and also producing a vacuum therein, the means illustrated in the drawings are suitable for this purpose and as there shown the same comprise a pump 29l having its inlet 30 connected with the atmosphere by means of a pipe 31 containing a valve 32 and its outlet 33 connected by means of a main pipe 34 having a valve 15 with the upper part of the impregnating chamber so that exterior atmosphere may be forced into the upper part of the creosote impregnating tank, whereby the liquid creosote in the lower part of this tank is forced into the vpores or interstices of the butt ends of the posts and the vapors in the upper part of this tank are forced into the top portions of the poles.

The pump 29 vmay also be used for producing a vacuum' in the creosote impregnating chamber for which purpose the main pipe 34y may be connected with the inlet of the pump by means of a branch pipe 43 containing a valve 44 and )the outlet of the pump may be connected with a branch delivery pipe 45 containing a valvev 46 for controlling the same. Between the main pipe dit upon operating this pump, the air from the till lliltl 34 and the outlet pipe- 33 is a valve 70 for controlling the same. as will presently apear. This branchy delivery pipe may lead directly to the atmosphere, if only air or vapors of no particular value are withdrawn from the impregnating chamber when drawing the vacuum therein. If, however, the vapors are valuable, as they wouldl be when consisting solely of creosote vapors. then the vapors discharged by the branch delivery pipe 45 are conducted by the latter into/ a condenser whereby these vapors are recovered and thuspermits of utilizing the same to advantage for impregnating other poles. While this condenser may be of any approved type, that shown in the drawings is typical of\onei suitable for this purpose, and consists of a condensing vat or chamber 47 adapted to be supplied at its lower end with water by means ofa suppl) pipe 48 containing a valve 49 while the warmed water is discharged from the upper end of this tank through an overiiow pipe 50 and a coil 51 arranged in the interior of this chamber and having its upper end connected with the branchvdelivery pipe of the pump 45 while its lower end is' connected with the upper end over again on of the creosote supply reservoir 10. By this means, the creosote vapors which are withdrawn from the impregnating tank are delivered to the condenser Where they are reduced to liquid form and then returned to the supply reservoir in condition to be used treated.

Instead of treating the tops or upper portions of the poles with vapor creosote which f is expensive, these parts of the poles may be treated with a protective material which is less eflicient than creosote, but adequate for this part of the poles on account of the reduced destructive effect of the elements on the same. Impregnating agents having such reduced preservative capacity are usually also less expensive and thereby reduce the cost of treating the pole in its entirety. A suitable preservative ,material for thus treating the tops of poles at reduced cost consists 'of a five percent solution of zinc chloride.

A supply of this zincchloride ,solution is stored in a reservoir 52 from which the same may be withdrawn and delivered into the zinc-chloride impregnating tank 100` preferably at the lower end thereof and also poles which are subsequently/ withdrawn therefrom by means of a pump 53 havingits inlet 54 connected with the lower end of the zinc-chloride reservoir by means of a pipe 55 containing a valve 56 and with the bottom of the zine-chloride impregnating tank by means of a by pass pipe 58 containing a valve 57, a branch pipe 59 leading to the bottom of the impregnating'tank and containing a valve 68, and the outlet 64 of the pump 53 being connected with the lower end of the ,zinc-chloride reservoir by meansof a pipe 65 containing a valve 66 and also connected with the by-pass pipe 58 and the branch pipe 59 by means of a pipe 67 containing a valve 68.

The interior of the zinc-chloride. tank and its contents may be heated by a coil 61 in the lower part thereof, which coil is provided with a valve 62 for controlling the as steam or hot water. If desired. steam *may be admitted directly into the zinc-chloride tank through a pipe 35 containing a controllingr valve 36. The lower end of the zinc-chloride tank may also be connected with a pressure gage 37 and the upper part of the same may be connected with a safety valve 38. i

Any suitable form of gage may be. lem# ployed in connection with the impregnating tanks to indicatey the amount of material which is admitted to Athe same and the amount which is withdrawn therefrom.

A pressure-may be produced in the zincchloride tank by the pump 29 through the medium of a pipe 39 containing a controlling valve 40 and connecting Vthe zinc-chloride tank with the pipe 34.

the tops thereof, theJ method of procedurev would be as follows:

The group of poles 2 to be treated may be first placed in-an upright position within the vertical creosote impregnating chamber or tank and ythe cover secured over the top of the same, so that this chamber 'is her- Ineticallyv sealed. A batch of liquid creosote is then delivered by the pump 1.1 from the creosote reservoir 10 into the lower end of this impregnating tank, so as to fill the latter to a depth of about live feet, although this height may be varied to suit different requirements. Such delivery of the creosote from the reservoir to the impregnating tank may be effected by operating the pump 11 while the valves 20, 22 are open and the valves 19, 21 are closed. It would, of course, be possible to place the charge of creosote in the impregnating tank before the poles are pla-ced therein, but it is preferable to deliver the creosote into the impregnating tank after the poles have been sealed therein, inasinuch as this reduces the loss of vapors andj it is also more agreeable to t e workmen. After the creosote has been thus delivered to ,the impregnating tank, this creosote may be heated by introducing steam into the coil 26 which causes the liquid to enter more readily into the ores or interstices atrthe lower or butt en s of the poles, and also l,causes some of the creosote to be converte-d into vapor, which rises and envelopes the tops or those portions of the poles arranged above the level of the liquid creosote. If only a mild or light application 11 while the'valves 20, 22 are closed and the valves 19, 21 open, thereby-causing the creosote withdrawn from the impregnating tank to be discharged into the creosote reservoir 10. Thereafter the vapors within the impregnating tank are withdrawn therefrom by operating the pump 29 while the valves 32, 40, 7 0 are closed` and the valves 1 5. 44, 46

are openrsaid vapors bheing conducted to the condenser which converts then into liquid and returns the same to the creosote rservoir. The pump 29 is preferably operated so that upon withdrawing the vapors from the impregnating tank a vacuum will be produced 1n the latter and thus withdraw from Vthe pores of lthe poles any excesscreosote or pre-. servative which may be present therein,

thereby enabling this excess material to be saved and to be used for treating other poles.

vpressure is established within the creosote impregnating tank so as to drive the liquid creosote into the pores of the butt ends of the. poles, whichpressure may also be utilized to force .the creosote vapors into the# tops or upper portions of the poles and increase the preservative effect on 4the same. Upon operating the pump 29 while the valves 32, 70 are open and the valves 15, 4:0, 44, 46 are closed, external air will be forced into the upper part of the impregnating tank which will cause the creosote vaporsxtherein to be driven into the tops of the poles and the liquid creosote tobe forced into the lower or butt ends of the poles, the degree of penetration of the vapors and liquid being governed by the degree of pressure which is thus produced within the impregnating tank.

Afterl the poles have been thus treated heavily by strong liquid creosote at the butt ends thereof and lightly by means of weak creosote vapors at the top ends thereof, the

surplus liquid creosote may be again withdrawn from the lower end of the impregnating tank and the creosote vapors may be also withdrawn and condensed preparatory reservoir manner, the poles after being impregnated at the butt ends with liquid creosote and removed from the tank l are reversed or turned end for end and placed in an upright position in the zinc-chloride tank, the lid of the latter being closed to hermetically seal this tank. Then the pump 53 is operated while the valves 56, 68 are-opened andthe valves 57, 66 are closed, whereby the zinc-chloride solution is withdrawn from the reservoir 52 and discharged into the zincchloride inipregnating reservoir and discharged into the zincchloride impregnating tank 100 to a suilicient depth so that the tops ot the poles which are now lowermost, are submerged. f. 1

Iffdesired, a pressure may be produced in the zinc-chloride impregnating tank while the poles are submerged in zinc-chloride and thereby 'cause the liquid to penetrate the required extent into the wood of these poles depending upon the amount of pressure which is maintained. This pressure may be produced by operating the pump 29 so as to take air from the external atmosphere and force the same into the upper part 'of the impregnating tank 100 while the valves 32, 40, -70 are open and the remaining valves 52. When treating poles' in this to being returned to the creosote reservoir, associated with this pump closed. If dein the manner previously indicated. After sired, the zinc-chloride may be heated to thus treating the butts and tops of the poles facilitate the entrance of the same into the either with or without internal pressure and pores of the poles by opening the valves removing the preservative agents from the impregnating tank, the cover of the latter may be opened and the group of poles removed therefrom, preparatory to introducing another group of poles when the operations described are repeated.

During these operations, the pressure.

which is produced within the impregnating 'chamber may be carefully noted on the pressure gage 24 so that the desired degree of penetration is obtained in accordance with the character of the Wood under treatment or other conditions. This pressure, however,

can not exceed a predetermined limit, by reason of the employment of a safety valve' which will open when the pressure rises to a certain point and thus render the apparatus safe in operation.

If desired, steam may be introduced'into the upper part of the impregnating chamber by opening the valve 92 for the purpose of heating the vapors therein and causing the same to penetrate more deeply into the tops of the poles.v

l Instead of treating the poles with a pre-- servative consisting solely of creosote in liquid and vapor form, the upper ends or tops of the poles may be impregnated with a liquid preservative which is less expensive, but still sufficiently effective for all practical purposes, such for instance as a.v zinc- 62 of the steam coil 61.

After the poles have been thus treated with zinc-chloride, the chloride of zinc pump 53 is started, while the valves 57, 66 are open and the valves 68, 56 are closed, whereby the zinc-chloride is Withdrawn from the zinc-chloride impregnating tank and discharged into the reservoir 52. After the surplus zinc-chloride has been thus withdrawn from the tank 100 the lid of the latter may be opened and the completely impregated poles may be removed and dried preparatory to putting the same to their intended use.

If desired this method of treating the poles may bee'ected in atreverse order from that described, namely, the tops of the poles may be first treated with zinc chloride solution in the tank 100, then turned end for end and placed in a reverse position in the creosote tank for treating the butt ends of the same. i'

For conveniencein handling the poles in groups or bundles, a plurality of the same may be placed in a crate or holder 71, as shown in Fig. 2, which crate containing a load of polesor the like can' be readily lowered into and raised out of the tanks by a crane or derrick and thus expedite this work. j

Treatment of poles or the like with creochloride solution, which is stored in the sote and zinc-chloride at the opposite ends of the same in accordance with the above described method can be'eiected thoroughly and economically, inasmuch as the amount of preserving material entering the pores of the nol'es is positively under control and the surplus from each group of poles is recovered and used for treating succeeding groups. Not only is a considerable saving in material effected but also in time of completing the treatment and drying the poles since this process permits of accomplishing this work much more expeditiously than the methods heretofore used.

Instead of arranging the impregnating Xtanks in a perfectly vertical position as shown in the drawings the same may be inclined more or lessJ but for all practical purposes the 'same should not be inclined more than about forty-tive degrees to the horizontal, as shown at 200 in Fig. 3, and such an inclination is regarded as substantially upright for the purpose ot' practicing this invention.

.If desired the purpose 'otthis invention may be attained by bfirst placing the poles in one of the tanks or retorts, then filling the tank with creosote or other preservative material, so as to cover the entire surface of the poles, then withdrawing some of the preserving material so as to submerge the poles only partly, say a distance of four to 'six feet from the lower ends of the same, and then apply-ing air pregssure to the interiorof the tank, whereby the thin coating adhering to the upper part of the poles will be driven into the poles and furnish moderate protection and a maximum amount of preserving material in the lower part of the tank will be forced deeply into the lower part of the poles for-increasing the resistance of the same 'to decay` I claim as my invention: c Q

The hereindescribed method of treating opposite ends of a Wooden pole with preservatives having ldifferent degrees of decay resisting properties, which method consists in rst placing the entire pole in a vertical position within a tank containing in its lowerA part a liquid preservative of one strength so that only the lower end of the pole is submerged in said liquid while its upper end is above the liquid level, applying a certain degree of air pressure to the interior of saidy tank which drives the liquid preservative into the lower part of the pole and simultaneously subjecting the unsubmerged upper part of the pole-to the same air pressure, then reversing the pole end for end and placing the entire pole in this reversed position into a tank which contains a liquid preservative of a diiferent strength in which the last mentioned lower part 'of the pole is submerged while the last mentioned upper part thereof is unsubmerged, and then applying a diiferent degree of air pressure to the interior of the tank whereby the mass of preserving liquid is driven into the last mentioned lower part of the pole and the coating of preserving 'liquid is driven into the last mentioned unsubmerged part of the pole.

RALPH DOWNEY PRITTIE 

